(a) Field of the Invention
The invention relates to a vacuum roll-to-roll device and a manufacturing method of a roll-type substrate.
(b) Description of the Related Art
Attention to a flexible display device that is light and flexible and maintains device characteristics has been substantially increased together with rapid technique development of a display device. For a mass production of a low cost and high speed flexible display device, a continuous roll-to-roll process is necessary, rather than a batch type process that is based on a conventional glass substrate.
The roll-to-roll process is a process for executing formation of a thin film while unwinding/rewinding a polymer substrate made of a material such as polyethylene terephthalate (“PET”), polyethylene naphthalate (“PEN”), and polyethersulfone (“PES”) used to manufacture the flexible display device through an unwinding/rewinding roller, and has been largely researched as a high speed and mass production method for the flexible photoelectronic device of a next generation.
The process for forming the thin film may be generally executed in a high vacuum chamber. In the state that the roll-type substrate is placed inside the vacuum chamber, a shutter of the chamber is closed and air is withdrawn by a vacuum pump to form a vacuum. However, inflow of air is generated by minute cracks at an edge portion where the roll-type substrate and an O-ring of the shutter meet each other such that the vacuum degree inside the chamber is decreased.